#include <stdlib.h>
#include<stdio.h>
union U
{
	double a;
	int b;
};

char* test()
{
	char testchar[] = "test for str!";
	return testchar;
}

int main()
{
	U c;
	c.a = 0xffff;
	c.b= 5;
	printf("%f\n",c.a);

	char *s= test();
	printf(s);
}
